crank bolts

[idiburner]

hey everyone so 8 of my 9 crank bolts broke off flush with the crank where the flywheel goes. I was wondering whats the best way to get them out? or if I am lucky does were the botls go on the crank come off and have the ability to be replaced if I remove the rear main seal without replacing the whole crank.

92 f250 7.3idi 5speed 4x4 cclb thanks everyone

 

[BDCarrillo]

How/why did they break??

Heat, left hand drill bits, tap outs, fluted extractors, and one hell of a prayer. The part they fasten to is integral to the solid machined crank casting.

 

[laserjock]

Wow. They should have been installed with some type of sealant so heat may be required. I did a water pump on a 302 where I had about that kind of luck. All I can say is good luck.

 

[icanfixall]

I suggest a left hand drill bit. If these are the original bolts they probably will back out easily. Sealant is needed on the threads to stop any oil leak. Thos bolt holes are drilled thru the crank flange so oil can leak out past the threads. Thats why we use a dab of RTV on the front damper keyway. No RTV up there and you sure will have a leaker. BTW make sure you buy new factory bolts for the flywheel and use a thread sealant on them. The torque is 47 lbs.

 

[IDIoit]

ive found that with broken bolts, sometimes you cant get a good center on the broken bolt.
to "center punch" them, break out a die grinder, with a burr bit and hit it in the center.
then a left handed drill bit.
if it drills through, use easy-outs. some heat, and PB blaster. sometimes its easier to cook th existing loc-tite/sealent a couple of times and cooling it with PB.
might as well try.
but the question you should be asking is...
why in the h-e doublehockeysticks did they break?

 

[jaluhn83]

If you drill them get the best drill bits you can find new. Be very very careful to keep the hole centered and straight.

First thing I would try I think is welding a nut onto the broken surface and pulling it out that way. Should be a big enough bolt that this would be marginally doable.

The most common thing that happens though is that the hole is either off center, or one breaks a drill bit/easy out. Then you're really screwed and about the only way to cut it out is EDM or a plasma torch. Huge pain in the butt either way.

However, I would be much more concerned about the question of why 8 of 9 bolts are broken. Did they break off when you tried to take them out? Best guess I would have is they were majorly overtightened possibly combined with excessive use of locktite, which would make me wonder what else is screwed up.

 

[riotwarrior]

As there is no head to bolt anymore to create stretch AKA clamping force, these should then back out quite easily IMO.

I've had really good luck with the grabbit bolt extractor google it or youtube it, you will find what I'm talking about.

Good luck and yes NEW crank bolts, sealant and only torque required nothing more and use an accurate torque wrench.

JM2CW

 

[IDIoit]

yes NEW crank bolts,

you mean these bolts cannot be TIG welded back together?